Four years ago I painted a scrap piece of plywood with chalkboard paint, framed it with some 1×2 scrap boards and screwed it to our fence with deck screws. I didn’t know how long it would last, since chalkboard paint is not meant for exterior conditions.

The first two summers it held up great. But last summer I started to notice some water damage.

Well it didn’t survive this winter.

If your kids are at the age where you only need one for a year or two than you don’t have to worry about doing too much weather proofing. But if you want it to last a few more years, here is what I would do differently next time.